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1.
J Appl Microbiol ; 131(5): 2433-2447, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33896080

RESUMO

AIMS: The present research aimed to examine the use of magnetite nanoparticles (MNPs) in combination with phyto-beneficial rhizobacterium (PhBR) for improvement of applied N recovery (ANR) from urea fertilizer in rice grown under deficient and optimum watering conditions. METHODS AND RESULTS: The Bacillus sp. MR-1/2 was positive for acetylene reduction, phosphate solubilization and ACC deaminase activity at temperature ranges 35-45°C. In a pot experiment, urea, MNPs and Bacillus sp. MR-1/2 were applied either alone or in combination to rice plants grown in pots under water deficit and optimal watering conditions. Combined application of urea, MNPs and Bacillus sp. MR-1/2 increased the plant N content and ANR by 27 and 65%, respectively, over their respective control values in rice grown under optimum watering conditions, whereas these increases were 27 and 41%, respectively, in rice grown under water deficit conditions. This treatment also increased the kernel weight and plant dry matter by 36 and 60%, respectively, over control (urea alone) values in rice grown under water deficit conditions, whereas these increases were 31 and 21·8%, respectively, in rice grown under optimum watering conditions. Values of malondialdehyde (MDA) contents, ascorbate peroxidase (APX), catalase and ethylene concentration were higher in control treatment under both the watering regimes. The application of Bacillus sp. MR-1/2 either alone or in combination with MNPs and urea reduced MDA contents, APX, catalase and ethylene production in the rice plants. CONCLUSION: The combined application of MNPs+Bacillus sp. MR-1/2 reduced the N losses from applied urea, increased N uptake and ANR in rice, decreased MDA contents, APX and catalase activity and ethylene level in rice grown under deficit and optimum water conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: The application of MNPs together with Bacillus sp. MR-1/2 may help to increase ANR and rice productivity under water deficit conditions with low cost of production.


Assuntos
Bacillus , Nanopartículas de Magnetita , Oryza , Fertilizantes , Nitrogênio , Ureia , Água
2.
Environ Sci Pollut Res Int ; 23(3): 2651-62, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26432272

RESUMO

The recent food security issues, combined with the threats from climate change, demand future farming systems to be more precise and accurate to fulfill the ever increasing global food requirements. The role of nutrients such as nitrogen (N), phosphorous (P), and potassium (K) in stimulating plant growth and development is well established; however, little is known about their function, if applied in combination, in improving crop yields under environmental stresses like drought. The aim of this study was to evaluate the effects of combined foliar spray of supplemental NPK (NPKc) on physiological and biochemical mechanisms that enhance the drought tolerance potential of wheat for improved yield. Foliar NPKc markedly influenced the accumulation of osmoprotectants and activity of both nitrogen assimilation and antioxidant enzymes. It significantly improved the concentration of proline (66 %), total soluble sugars (37 %), and total soluble proteins (10 %) and enhanced the activity of nitrate reductase, nitrite reductase, catalase, and peroxidase by 47, 45, 19, and 8 %, respectively, with respect to no spray under water-deficit conditions which, in turn, improve the yield and yield components. The accumulation of osmolytes and activity of antioxidant machinery were more pronounced in drought tolerant (Bhakkar-02) than sensitive genotype (Shafaq-06).


Assuntos
Secas , Fertilizantes , Triticum/crescimento & desenvolvimento , Aclimatação , Antioxidantes/metabolismo , Catalase/metabolismo , Genótipo , Nitrogênio , Peroxidase/metabolismo , Peroxidases/metabolismo , Fósforo , Potássio , Estresse Fisiológico , Água/metabolismo
3.
Br J Cancer ; 97(3): 391-7, 2007 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-17609662

RESUMO

In contrast to early breast cancer, the prognostic effect of tumour angiogenesis in tumours with advanced axillary spread has been less studied. We retrospectively analysed the effect of microvessel density (MVD) and vascular endothelial growth factor (VEGF) by immunohistochemistry on the outcome of 215 patients treated uniformly within prospective trials of high-dose chemotherapy for 4-9 and >/=10 positive nodes, and followed for a median of 9 (range 3-13) years. Microvessel density was associated with epidermal growth factor receptor (EGFR) expression (P<0.001) and tumour size (P=0.001). Vascular endothelial growth factor overexpression (51% of patients) was associated with overexpression of EGFR (P=0.01) and HER2 (P<0.05), but not with MVD (P=0.3). High MVD was associated with worse relapse-free survival (74 vs 44%, P<0.001) and overall survival (76 vs 44%, P<0.001). Vascular endothelial growth factor overexpression had no effect on outcome. Multivariate analyses showed a prognostic effect of MVD independently of other known prognostic factors in this patient population. In conclusion, tumour angiogenesis, expressed as MVD, is a major independent prognostic factor in breast cancer patients with extensive axillary involvement.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/irrigação sanguínea , Neovascularização Patológica , Fator A de Crescimento do Endotélio Vascular/metabolismo , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Relação Dose-Resposta a Droga , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico
4.
Exp Cell Res ; 229(2): 350-9, 1996 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8986618

RESUMO

Nuclei of multinucleate cells generally initiate DNA synthesis simultaneously, suggesting that the timing of DNA synthesis depends upon the appearance of a cytoplasmic signal. In contrast, intact nuclei from quiescent mammalian cells initiate DNA synthesis asynchronously in cell-free extracts of Xenopus eggs, despite the common environment. Here we show that the two nuclei of permeabilized binucleate cells enter DNA synthesis coordinately in egg extracts, as they do in vivo, with different pairs of nuclei initiating replication at different times. This indicates that the two nuclei of a binucleate cell are identical in their sensitivity to the inducers of DNA synthesis in egg extracts; this sensitivity varies in general between the nuclei of unrelated cells. The asynchrony of DNA synthesis shown by unrelated nuclei in egg extracts is therefore not an artifact of the cell-free system but a reflection of genuine differences preexisting within the intact cell. Evidence that these differences between nuclei are responsible for a substantial fraction of G1 variability in living cells is presented.


Assuntos
Ciclo Celular/fisiologia , Núcleo Celular/metabolismo , Citoplasma/metabolismo , DNA/biossíntese , Animais , Fusão Celular , Sistema Livre de Células , Meios de Cultura , Feminino , Fase G1/fisiologia , Técnicas In Vitro , Óvulo/metabolismo , Fase de Repouso do Ciclo Celular/fisiologia , Fase S/fisiologia , Fatores de Tempo , Xenopus
5.
J Immunol ; 164(5): 2575-84, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10679096

RESUMO

We demonstrated that IL-12 was induced during primary or secondary pulmonary adenoviral infection in wild-type (wt) mice. However, cellular responses were not compromised in the lungs of IL-12-/- mice. The level of IFN-gamma in the lung was similar in wt and IL-12-/- mice during pulmonary viral infection. Upon Ag stimulation in vitro, lymphocytes from draining lymph nodes or spleen of infected IL-12-/- mice released large amounts of IFN-gamma, but not IL-4, which were comparable to those released by wt lymphocytes. Furthermore, a predominantly IgG2a response to adenoviral infection was unimpaired in IL-12-/- mice. These significant anti-adenoviral Th1-type responses in IL-12-/- mice led to an efficient clearance of virus-infected cells in the lung. Whether IL-18 was involved in IL-12-independent anti-adenoviral immune responses was investigated. Abrogation of endogenous IL-18 by an Ab resulted in diminished IFN-gamma release and lymphocytic infiltrate in the lung during adenoviral infection. Nevertheless, the development of lymphocytes of the Th1 phenotype was unimpaired in the absence of both IL-12 and IL-18. In contrast to their intact ability to mount Th1-type responses to viral infection, IL-12-/- mice suffered impaired Th1-type immune responses to pulmonary mycobacterial infection. Our findings suggest that IL-12, although induced, is not required for Th1-type responses to respiratory viral infection, in contrast to mycobacterial infection. IL-18 is required for the optimal release of IFN-gamma in the lung during viral infection, but is not required for the generation of virus-reactive Th1-type lymphocytes. Th1 differentiation during respiratory adenoviral infection may involve molecules different from IL-12 or IL-18.


Assuntos
Infecções por Adenoviridae/imunologia , Quimiocinas CC , Interferon gama/metabolismo , Interleucina-12/fisiologia , Interleucina-18/fisiologia , Pneumopatias/imunologia , Pulmão/imunologia , Células Th1/imunologia , Células Th1/virologia , Infecções por Adenoviridae/metabolismo , Infecções por Adenoviridae/patologia , Adenovírus Humanos/imunologia , Animais , Anticorpos Antivirais/biossíntese , Diferenciação Celular/imunologia , Quimiocina CCL11 , Citocinas/biossíntese , Citocinas/genética , Feminino , Regulação da Expressão Gênica/imunologia , Imunofenotipagem , Interleucina-12/deficiência , Interleucina-12/genética , Pulmão/metabolismo , Pneumopatias/metabolismo , Pneumopatias/patologia , Linfonodos/imunologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mycobacterium bovis/imunologia , Baço/imunologia , Células Th1/metabolismo , Células Th1/patologia , Transgenes/imunologia , Tuberculose Pulmonar/imunologia
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